This application relates to methods and devices for remote internal inspection and ablation/modification of an object disposed within a mass.
Methods for internal inspection of objects are known. Modern approaches typically use sonar methods for probing and/or altering the internal composition of a mass by applying acoustic waves to the mass, measuring the vibrations induced in the excited mass such as by detecting scattered acoustic waves, and modifying subsequently applied acoustic waves in accordance with the scattered waves. For instance, U.S. Pat. No. 5,092,336 to Fink describes a method for focusing acoustic waves on a target in tissue wherein the tissue containing the target is illuminated with an unfocused acoustic beam, echo signals received by an array of electro-acoustic transducers are stored, the distribution in time and the shapes of the echo signals are reversed, and the reversed signals are applied to the transducers in the array to illuminate the tissue.
In U.S. Pat. No. 6,490,469 to Candy, the use of time reversed echo signals is expanded to a method for decomposing a plurality of scatterers in tissue by iteratively transmitting a time reversed field into the plurality of scatterers of the medium and performing a sequence of time-reversal iterations to extract contribution of the i-th scatterer of the plurality of scatterers, estimating a weighting coefficient of the i-th scatterer of the plurality of scatterers, and estimating the plurality of scatterers of the medium with the i-th scatterer removed, until a decomposition condition has been satisfied.
These methods and devices, and others like them, have met with practical success and have been applied to a variety of uses. However, they are limited by their use of acoustic transducers for exciting the target and surrounding mass and for applying the reversed signals to the mass, as well as for measuring the vibrations of the excited mass. What is still needed are methods and devices for remotely focusing energy on a mass to locate and/or destroy or otherwise alter targets disposed therein. The present embodiments answer this and other needs.